Polystachya comprises ca. 200 epiphytes and terrestrial species with a Pantropical distribution. The species of this genus are highlighted because of neither the pedicel nor the ovary resupinate, so the lip is positioned in the uppermost position in the flower. This study aimed to do the taxonomic treatment of Polystachya in Paraná state, presenting the descriptions, plates, distribution maps, identification key, conservation status, comments for each species. Four species are found for the state of Paraná, being the first record of P. rupicola. The genus occurs predominantly in the Floresta Ombrófila Densa, with some records in Floresta Ombrófila Mista and Estepe Gramíneo Lenhosa in the state. According to the criteria of the IUCN, P. rupicola can be considered as critically endangered and P. caespitosa, P. caracasana and P. concreta as endangered due to the habitat destruction and indiscriminate collection. A lectotype is proposed for P. caespitosa.
biodiversity; flora of Paraná; IUCN; Atlantic Forest; monocots